In August 1940, just a few days before German bombs began raining down on London, Americans flocked to movie theaters to see a spine-tingling spy thriller whose story was unsettlingly close to real life. Directed by Alfred Hitchcock, the film, called Foreign Correspondent, focuses on Johnny Jones, a newspaper reporter in New York, who at the beginning cares little or nothing about the growing threat of war in Europe. After being transferred to London, Jones, played by Joel McCrea, is pitchforked into a surreal world of assassinations, fifth columnists, and murderous Nazi spies. No longer apathetic about Germany’s danger to the world, he becomes a fierce champion of the anti-Nazi cause.

In the movie’s last scene, Jones, in the midst of a Luftwaffe air raid on London, makes an impassioned radio broadcast to listeners in America, in effect urging them to ditch their isolationism and come to the aid of an imperiled Europe. With lights flickering and an air raid siren wailing in the background, he declares: “All that noise you hear…is death coming to London. You can hear the bombs falling on the streets and the homes. Don’t tune me out — this is a big story and you’re part of it…The lights are all out everywhere, except in America. Keep those lights burning…Hang on to your lights, they’re the only lights left in the world.”

The Reich’s Joseph Goebbels, a master of propaganda himself, couldn’t help but admire what he called “a masterpiece of propaganda, a first-class production which no doubt will make a certain impression upon the broad masses of the people in enemy countries.” Isolationist Sen. Gerald Nye was less complimentary about Hitchcock’s movie — and the flood of other anti-Nazi films that had poured out of Hollywood after the German conquest of most of Europe in the spring and summer of 1940. In a radio rant, Nye called the movie studios “the most gigantic engines of war propaganda in existence…. The truth is that in 20,000 theaters in the United States tonight, they are holding mass war meetings.”

Neither Hitchcock nor Walter Wanger, Foreign Correspondent’s producer, however, was remotely apologetic about the movie’s obvious message — that America must enter World War II. Wanger, one of the film industry’s few successful independent producers, made it clear that his goal in making Foreign Correspondent was “to shake the U.S. into an awareness of what must threaten her if she turned her back on Europe.” Wanger’s staunchly interventionist viewpoint was hardly a minority opinion in Hollywood. Four years before, energized by the growing threat of Nazi Germany, hundreds of screenwriters, directors, actors, and producers had come together to form the Hollywood Anti-Nazi League, which became the focal point of liberal, interventionist activity in the film community. Intent on raising the industry’s political consciousness, the league sponsored rallies, mass meetings, and letter-writing campaigns for a wide array of causes. By contrast, America First, the country’s leading isolationist organization, found it virtually impossible to recruit members in the film industry. One of the few prominent Hollywood figures who did enlist was the actress Lillian Gish, who became a member of America First’s national committee. Not long afterward, however, Gish resigned from America First after producers made clear they wouldn’t hire her as long as she belonged to the organization.

The British members of the Hollywood community, which included Hitchcock, Cary Grant, Ronald Colman, and Cedric Hardwicke, tended to be the most zealous interventionists of all. Many of them worked closely with the Churchill government to promote Britain and its war effort and to encourage the U.S. to enter the conflict. They were joined by an influx of British directors and writers who flooded into the film capital to help in the propaganda effort. Two of those budding British propagandists — playwright R.C. Sheriff and novelist James Hilton — worked together to write Mrs. Miniver, about the experiences of an upper-middle-class family in the London suburbs at the time of Dunkirk and the Blitz. An enormous hit, Mrs. Miniver, with its story of British resolution and courage in the midst of catastrophe, touched the hearts of millions of Americans. Churchill called it “propaganda worth a hundred battleships”; its American director, William Wyler, called himself a “warmonger” and acknowledged he made Mrs. Miniver because “I was concerned about Americans being isolationists.”

Prominent isolationists like Charles Lindbergh and Sens. Gerald Nye and Burton Wheeler continued to complain bitterly about the “war hysteria” being fomented by the movie studios, but their attempts to regulate the political content of films met with utter failure. Hollywood’s victory over its isolationist foes emboldened it to remain in the forefront of national debates over contentious political issues. Indeed, the film industry’s activism against the dictators in the prewar years was its “political coming out party.” From then on, leading Hollywood figures would have no qualms about making their voices heard on major national and international matters — a situation that still holds true today.

I love reading spy novels, especially those by Alan Furst, who’s one of my favorite writers. No one is better at evoking the flavor of life — the danger and excitement — of such exotic locales as pre-World War II (and wartime) Paris, Warsaw, Moscow, Berlin, Budapest, and Salonika.

Furst has yet to turn his attention to the United States as a setting for one of his historical novels. But if he did, he would find wonderful material to work with, particularly in New York City. For, as it happened, New York, too, was a hotbed of spying, particularly in the turbulent days before America entered World War II. Its nerve center was the International Building, a Rockefeller Center skyscraper that faced St. Patrick’s Cathedral on Fifth Avenue. From there, the British government conducted an extraordinary covert intelligence operation, whose sole purpose was to force the United States into the war.

With the knowledge and tacit permission of President Roosevelt and FBI chief J. Edgar Hoover, this unconventional outfit, which employed more than one thousand people at its Rockefeller Center base, planted propaganda in American newspapers, spied on isolationist groups and pro-Axis diplomats, dug up political dirt on isolationists in Congress, and forged documents that, when brought to public attention, helped stir up anti-Nazi sentiment. Its intentionally bland name was the British Security Coordination, and its head was William Stephenson, a shadowy, secretive multimillionaire businessman from Canada whom Winston Churchill tapped to oversee this top-secret, “ungentlemanly warfare” organization. (Novelist Ian Fleming, a friend of Stephenson’s, would later use him as a model for Fleming’s famed fictional character, James Bond.)

At this point, the United States was still officially neutral, and the BSC’s activities were a clear violation of U.S. law. But the Roosevelt administration turned a blind eye, and the British took full advantage ot that. They joined forces with several American interventionist organizations, giving them information that British agents had uncovered and, in some cases, reportedly helping to subsidize them. One of those groups was called Fight for Freedom; its membership list was a Who’s Who of the East Coast’s business, academic, and cultural elites, and its offices were also in the International Building. Fight for Freedom joined with British operatives to disrupt and harass rallies and other gatherings of the America First Committee, the country’s most influential isolationist organization. Along with other private interventionist groups, it also placed spies inside the offices of America First, as well as those of isolationist members of Congress and organizations suspected of German ties, to eavesdrop on conversations and secretly photograph incriminating letters and other documents.

Nazi Germany had its own spies in New York and throughout the rest of the country, but compared to the British, they were pathetically inept and ineffective. Hans Thomsen, the No. 2 man in the German embassy in Washington, repeatedly complained to his superiors about how bad the Reich’s operatives were, fuming that their operations were “marked by naivete and irresponsible carelessness, and on top of that, lacked any kind of coordination.” Of course, they also faced problems that the British didn’t have: instead of being in league with the FBI as the British were, the Germans were spied on by both the FBI and the British.

In late 1940, a German-born U.S. citizen named William G. Sebold opened an office in the Knickerbocker Building in downtown Manhattan. The office actually was a meeting place for a couple of dozen spies working in the New York area for Germany’s military intelligence agency, the Abwehr; Sebold’s job was to transmit their reports back to Berlin. Unbeknownst to the German operatives, their conversations with Sebold about their past feats and future plans were being recorded by FBI bugs and cameras. Sebold, the ace radio operator, was, as it turned out, a double agent, who had been working with the FBI all along. In July 1941, the spies were rounded up by the FBI and later put on trial. The mass arrests were a debacle for Germany, a point underscored by an exasperated Hans Thomsen in an “I-told-you- so” cable to Berlin: “It can be assumed that the American authorities had long known all about the network, which certainly would not have been any great feat, considering the naïve and sometimes downright stupid behavior of these people.”

Yet the ineptness of the German agents went largely unmentioned by the FBI when it trumpeted to the American public its success in breaking up the spy network. According to Attorney General Robert Jackson, “the Nazis never had an extensively organized espionage or sabotage ring in this country.” Indeed, the United States never faced any serious threat of internal subversion before or during the war. But the American people never knew that; in fact, they were told the opposite. According to the FBI, the White House, and the British, the roundup of the German spies was inconvertible proof that swarms of fifth columnists and enemy agents were busily at work throughout the country — a belief that’s still conventional wisdom today.

John F. Kennedy, Gerald Ford, Kurt Vonnegut, Potter Stewart, Gore Vidal, Sargent Shriver, Kingman Brewster — all household names in mid and late twentieth-century America. But earlier in their lives, they had something else in common. In the late 1930s and even into the 1940s, they were passionately opposed to the idea of American involvement in World War II.

Today, that war is known as the “good war” — a necessary conflict to save Western civilization from the evil of Nazi Germany. But in the years before Pearl Harbor, the extent of that evil was not as obvious as it is now, and millions of Americans — notably college students, who would be among the first to fight — revolted against the very thought of U.S. participation in another bloody European war. “The conduct of World War I, with the years of stalemate, the slaughter of millions–all this chilled our marrow,” recalled CBS’s Eric Sevareid, who, as a student at the University of Minnesota, participated in pacifist demonstrations in the mid-1930s. During that period, more than half a million American undergraduates signed a pledge refusing to serve in the armed forces in the event of another conflict. As war swept over Europe in 1939 and 1940, thousands of students across the country took part in antiwar protests; at the University of Missouri, students held up signs reading “The Yanks Are NOT Coming.”

College students were also responsible for the formation of the America First Committee, which, within months of its creation in the summer of 1940, emerged as the most powerful, vocal, and effective isolationist organization in the country. Although America First is generally viewed as the embodiment of conservative, Midwestern isolationism, it was actually born on the Yale campus — the brainchild of a group of top campus leaders. A key founder was Kingman Brewster, a Yale junior who would later become president of Yale and U.S. ambassador to Britain. Also in the group were Potter Stewart, a future justice of the Supreme Court, and his close law school friend, Sargent Shriver, who two decades later would be appointed first head of the Peace Corps. Another participant was law student Gerald Ford, a former All-American football player at the University of Michigan and future president of the United States.

The group kicked off its campaign by circulating antiwar petitions on campuses throughout the East and recruiting other students and recent graduates to lead opposition to American involvement. Nearly half the undergraduates at Yale signed the petitions, with similar numbers reported at other colleges. Hundreds of students agreed to spend the summer of 1940 as organizers, and many more sent money to help the effort. Among the donors was Harvard senior John F. Kennedy, whose $100 check was accompanied by a note that said, “What you are all doing is vital.” Meanwhile, fifteen-year-old Gore Vidal was busy establishing an America First chapter at Phillips Exeter, the exclusive prep school he attended in New Hampshire.

With its emergence on the national stage, America First moved its headquarters to Chicago, From then on, most of its leaders would be Midwestern businessmen, whose social and political views were considerably more conservative than those of its idealistic young founders. By the time of Pearl Harbor, most of the Yalies who had founded America First had drifted away from the organization; when the United States finally entered the war, they, along with the vast majority of other college antiwar activists, enlisted in the fight.

Sargent Shriver — who, like his brother-in-law, John F. Kennedy, was injured during the war — was one of the few people associated with America First who had no qualms later about publicly discussing his prewar isolationism. “Yes, I did belong to AMERICA FIRST,” he wrote. “I joined it because I believed at the time we could better help to secure a just settlement of the war in Europe by staying out of it. History proved that my judgment was wrong, neither for the first time nor the last.” Later, Shriver would tell a journalist: “I wanted to spare American lives. If that’s an ignoble motive, then I’m perfectly willing to be convicted.”

Before I began my research for Those Angry Days, I knew that Charles Lindbergh had been a major supporter of the American isolationist movement before Pearl Harbor. But I had no idea that he was, in fact, the unofficial leader of that movement, nor was I fully aware of his status as Franklin Roosevelt’s main enemy in the fight over America’s involvement in World War II. As the two most famous men in the country, Lindbergh and Roosevelt both had an enormous impact on public opinion, and they took advantage of that fact as they battled each other for Americans’ hearts and minds. Their duel was bitter, brutal, and utterly fascinating, and I decided to make it the central focus of my book about America’s debate over its wartime role.

On the surface, the two men could not have been more different. Roosevelt was a natural politician, who, from the beginning of his career, loved shaking hands, slapping backs, working a crowd, and cultivating the press. Full of exuberance and joie de vivre, he used his extraordinary charm and charisma to bedazzle everyone he met. Being around FDR, Winston Churchill once memorably said, was like opening your first bottle of champagne.

Charles Lindbergh couldn’t have been more different. A loner all his life, he was an aloof, emotionally reticent man who was uncomfortable around people and regarded conversation, in the words of his wife, “as though it were a business transaction or a doctor’s pill that he has to take.” He scorned politics and hated the press.

Yet the aviator and the president were more alike than most people realized. For all his apparent sociability, Roosevelt was, like Lindbergh, essentially a reserved, self-sufficient figure. In the view of Arthur Schlesinger Jr., FDR was “glittering, impersonal, superficially warm, basically cold.” There were other similarities. The two men were both strong-willed and stubborn, believing deeply in their own superiority and having a sense of being endowed with a special purpose. They were determined to do things their own way, were slow to acknowledge mistakes, did not take well to criticism, and insisted on being in control at all times.

Even before the pre-Pearl Harbor debate, they already had a history with each another. In early 1934, Lindbergh, in what Gore Vidal called “a mano a mano duel,” challenged Roosevelt’s cancellation of air mail delivery contracts granted by his predecessor, Herbert Hoover. Lindbergh won that round, and FDR never forgave him. In the isolationist-interventionist fight, though, Roosevelt was on surer ground. A masterful politician, the wily — and sometimes ruthless — president would end up giving the political neophyte a wrenching lesson he would never forget, one that contributed to the tarnishing of his reputation for generations to come.

What I like most about writing books is not the actual writing — to me, that’s about the hardest work there is– but all the research I do before the slog of sitting down at the computer. What’s particularly fun is running across a new and unexpected nugget of information about my subject. Not something dramatic or sensational, usually, but just a little bit of history that adds color and life to the story I’m telling.

In Those Angry Days, one of the most interesting nuggets has to do with Dr. Seuss, probably the most beloved author of children’s books in this country. As it turned out, Theodor Seuss Geisel — Dr. Seuss’s real name — did not always focus on children as his audience. Before America entered World War II, Geisel, a Dartmouth graduate who’d also attended Oxford, made his living as a humor writer for popular magazines and as an ad illustrator for several major U.S. companies, including Standard Oil. Then, in 1941, he was hired as an editorial cartoonist for PM, a new, left-leaning New York daily newspaper that advocated an immediate U.S. declaration of war against Nazi Germany.

Geisel’s pen became one of the most potent weapons in the arsenal of American interventionism. Using the knife-sharp wit and whimsical surrealistic animals that became the trademarks of his books, his cartoons skewered both Axis leaders and American isolationists. Next to Hitler, his favorite subject was Charles Lindbergh, the unofficial leader of the American isolationist movement. In one Dr. Seuss cartoon, a group of ostriches (the ostrich was Geisel’s symbol for isolationism) marches down a street carrying a sign reading “Lindbergh for President in 1944!” while several sinister black-hooded figures, labeled “U.S. fascists,” follow with their own sign: “Yeah, but why wait until 1944?” In another, a smiling whale dances on a mountaintop, singing: “I’m saving my scalp/Living high on an Alp/Dear Lindy!/ He gave me the notion!”

Geisel was also fond of savaging America First, the country’s biggest and most influential isolationist organization. One of his best 1941 cartoons featured a mother, labeled “America First,” reading a book called Adolf the Wolf to her frightened children. The caption reads: “…and the wolf chewed up the children and spit out their bones…But those were Foreign Children, and it really didn’t matter.”

Asked many years later about the rationale behind his scathingly funny wartime cartoons, Geisel gave a simple answer: “I just wanted the good guys to win.”

A highly polarized country. A savagely partisan Congress. A brutal presidential race, which ended with the Democratic incumbent defeating his Republican challenger, an ex-businessman.

This was America in 1940 and early 1941 — a period that I write about in my new book, Those Angry Days, and one that bears striking parallels to today’s poisonous political climate. Just as now, Americans were engaged in a bitter debate over the future direction of their country. World War II had just begun, and the question was: Should the traditionally isolationist U.S. come to the aid of Britain, the last European nation holding out against Hitler? President Roosevelt and other interventionists said yes, believing that Britain’s survival was crucial to America’s economic and physical security. The country’s isolationists, a predominant force in the Republican party, argued that the United States was in no danger and must focus only on its own defense. Just as today, the president’s re-election made no difference to his Republican congressional foes, who steadfastly refused to cooperate with him and his policies.

There was, however, one vital difference between then and now. In the midst of all the polarization and gridlock, a few prominent Republicans stepped up to do what they thought was right, defying their party and putting the interests of their nation and its people ahead of political ambition and partisan advantage.

The chief rebel was none other than Wendell Willkie, the 1940 GOP candidate for president. Instead of pulling a Mitt Romney-like disappearing act after the election, Willkie went on the radio to announce to the American people: “We have elected Franklin Roosevelt president. He is your president. He is my president…We will support him.”

To the fury of the Republican old guard, Willkie endorsed 1941 legislation creating the Lend Lease program, sending aid to Britain, as well as backing the first peacetime draft, which made possible the huge U.S. Army and Air Force that took the field after Pearl Harbor. Roosevelt, who would later describe his former foe as “a godsend to this country when we needed him most,” acknowledged that Willkie’s support for those measures, both of which were crucial in winning the war, might well have made the difference between congressional victory and defeat.

Joining Willkie as GOP apostates were Henry Stimson and Frank Knox, the country’s two most respected Republican senior statesmen, who became members of Roosevelt’s cabinet and who, like Willkie, were essentially read out of their party. Neither much cared. As Knox told his friends, “I am an American first, and a Republican afterward.”

Like Stimson and Knox, Wendell Willkie has disappeared into the mists of history, recalled, if at all, merely as one of FDR’s defeated rivals. He deserves much more. Noting Willkie’s moral courage and political leadership, MSNBC’s Chris Matthews recently wrote, “I long for such a leader today.”